ZyXEL VMG4825 User Guide - Page 147
IEEE 802.1Q Tag
View all ZyXEL VMG4825 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 147 highlights
Chapter 10 Quality of Service (QoS) Table 51 Policer Setup: Add/Edit LABEL Meter Type DESCRIPTION This shows the traffic metering algorithm used in this policer. The Simple Token Bucket algorithm uses tokens in a bucket to control when traffic can be transmitted. Each token represents one byte. The algorithm allows bursts of up to b bytes which is also the bucket size. The Single Rate Three Color Marker (srTCM) is based on the token bucket filter and identifies packets by comparing them to the Committed Information Rate (CIR), the Committed Burst Size (CBS) and the Excess Burst Size (EBS). Committed Rate Committed Burst Size The Two Rate Three Color Marker (trTCM) is based on the token bucket filter and identifies packets by comparing them to the Committed Information Rate (CIR) and the Peak Information Rate (PIR). Specify the committed rate. When the incoming traffic rate of the member QoS classes is less than the committed rate, the device applies the conforming action to the traffic. Specify the committed burst size for packet bursts. This must be equal to or less than the peak burst size (two rate three color) or excess burst size (single rate three color) if it is also configured. Conforming Action This is the maximum size of the (first) token bucket in a traffic metering algorithm. Specify what the VMG does for packets within the committed rate and burst size (greenmarked packets). NonConforming Action Available Class • Pass: Send the packets without modification. • DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to use. Specify what the VMG does for packets that exceed the excess burst size or peak rate and burst size (red-marked packets). • Drop: Discard the packets. • DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to use. The packets may be dropped if there is congestion on the network. Select a QoS classifier to apply this QoS policer to traffic that matches the QoS classifier. Selected Class Highlight a QoS classifier in the Available Class box and use the > button to move it to the Selected Class box. OK Cancel To remove a QoS classifier from the Selected Class box, select it and use the < button. Click OK to save your changes. Click Cancel to exit this screen without saving. 10.8 Technical Reference The following section contains additional technical information about the VMG features described in this chapter. IEEE 802.1Q Tag The IEEE 802.1Q standard defines an explicit VLAN tag in the MAC header to identify the VLAN membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user priority. The VLAN ID associates a frame with a specific VLAN and provides the information that devices need to process the frame across the network. VMG4825-B10A User's Guide 147